Extract a Bit Field from a 32-bit Register

Code

#include <stdio.h>
#include <stdint.h>

uint32_t extract_field(uint32_t reg, uint8_t pos, uint8_t len) {
    \/\/ Your code here
    uint32_t mask = ((1 << (len + 1)) - 1);
    return (reg >> pos) & mask;
}

int main() {
    uint32_t reg;
    uint8_t pos, len;
    scanf("%u %hhu %hhu", &reg, &pos, &len);
    printf("%u", extract_field(reg, pos, len));
    return 0;
}<\/code><\/pre>Solving Approach<\/strong><\/h2>Try to think 2 part : position, &#160;mask<\/strong><\/p>&#160;<\/h2>&#160;<\/h2>"}

Solving Approach

Try to think 2 part : position,  mask

Solution use 1U instead of 1

uint32_t extract_field(uint32_t reg, uint8_t pos, uint8_t len) {
    // Move the desired bits to the rightmost side
    // Then apply a mask to get only those bits
    return (reg >> pos) & ((1U << len) - 1);
}

 

 

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Input

3060793344 28 4

Expected Output

11